Packer device having a j-latch and seal means

ABSTRACT

A bypass control for a packer device. A seal means in the form of a piston assembly is reciprocatingly received within an annulus formed between a mandrel, a housing, and the main body portion of a packer device. A J-latch mechanism is jointly formed between an upper portion of the main body and the housing. A circumferentially extending seal surface is formed between the housing and the piston. When the J-latch is &#39;&#39;&#39;&#39;set,&#39;&#39;&#39;&#39; pressure differential across the piston forces it into a position to seal off a passageway which otherwise communicates the lower extremity of the packer with the J-latch assembly; and accordingly, precludes fluid pressure from below the packer causing flow to occur through the J-latch assembly. This expedient additionally enables the seal means to control the action of a set of gripping elements radially disposed about an area located up-hole of the packer elements, as well as to provide a means by which fluid can be bypassed through the packer device.

United States Patent 1191 Watson Dec. 24, 1974 PACKER DEVICE HAVING A J-LATCH AND Primary ExaminerDavid H. Brown SEAL MEANS Attorney, Agent, or FirmMarcus L. Bates [76] Inventor: Billy Ray Watson, 1000 S. Franklin,

Monahans, Tex. 79756 [57] ABSTRACT [22] Flled' Nov. 1973 A bypass control for a packer device. A sea] means in PP 90 the form of a piston assembly is reciprocatingly re- Related Application Data ceived within an annulus formed between a mandrel, a [63] Continuation-impart of Ser. No. 194 326 Nov 1 and the mam pody peo-mon of a packer de- 1971 abandonei v1ce. A J-latch mechamsm 1s omtly formed between an upper port10n of the mam body and the housmg. A

' circumferentially extending seal surface is formed beiiii iiifi'gillll'fllill'lllll. ii kgi $16 293; eweee ehe heeeee eee e eeeeewhen the J-leeeh 1 [58] Field of g 166,120 5 129 130 set, pressure differentlal across the piston forces 1t 8 into a pos1t1on to seal off a passageway wh1ch otherwise communicates the lower extremity of the packer [56] References Cited with the J-latch assembly; and accordingly, precludes fluid pressure from below the packer causing flow to UNITED STATES PATENTS occur through the J-latch assembly.

This expedient additionally enables the seal means to 3:338:308 8/1967 ElllStOl'l at 61.11:: :11: 166/120 the of a t of grppmg elements 3,356,142 12/1967 Crow et al. 166/134 radially disposed abut l mated "1 of the 3,412,301 11/1963 Young 166/120 packer elements, as well as to provide a means by 3,416,609 12/1968 Kil ore 166/134 X which fluid can be bypassed through the packer 3,426,846 2/1969 Young l66/l29 device. 3,508,610 4/1970 Kisling 166/120 11 Claims, 8 Drawing Figures PATENTEU [1EC24 I974 FIG. 1

SHLU 1 [IF 3 FIG. 2

' PACKER DEVICE HAVING A J-LATCH AND SEAL MEANS RELATED PATENT APPLICATIONS This is a continuation in part of Pat. application Ser. No. 194,326 filed Nov. 1, 1971, now abandoned.

BACKGROUND OF THE INVENTION Well packers are disposed downhole in a well bore for the purpose of isolating lower portions of a bore- QI from yrzpe lzqr ons the e f S we laaslssts have an anchor disposed below the packing element which is manipulated by a tubing string in various manners so as to anchor the packer device at a specific predetermined downhole location. Thereafter, the packer element itself is set thereby precluding fluid flow between the annulus formed between the packer and the borehole. Gripping elements are usually provided on the packer device at a location spaced from and above the packer elements, and often the lower anchor device is of a design which enables manipulation of the tubing string to unseat or relax the upper gripping elements and to unset the packer element so as to enable the packer to be placed at a different selected elevation within the borehole.

The prior art discloses details of construction and operation of various packer devices, such as exemplified by the patents to Clark Jr. et al, U.S. Pat. No. Re. 25,639 and Keithahn, US. Pat. No. 3,112,795, to which reference is made forfurther background of this invention.

It is desirable to have a resetable and retrievable packer combination having means thereon for automatically preventing fluid flow across the J-latch assembly thereof when the J-latch is in the set or latched configuration.

SUMMARY OF THE INVENTION This invention relates to apparatus for controlling fluid flow across coacting members of a packer apparatus which are releasably held together by a J-latch assembly. The packer mandrel is affixed to a housing which is concentrically arranged respective to the packer body and the mandrel. The housing is spaced from the body to form an annular flow chamber. A piston is reciprocatingly received within the chamber and movable into sealing engagement with the housing to thereby preclude fluid flow through the chamber and across the J-latch assembly.

In a packer device, the apparatus provides for a bypass which controls the action of a set of gripping elements, as well as prevents fluid flow across a J-latch.

A primary object of this invention is the provision of a seal means in combination with a packer apparatus for preventing fluid flow. thereacross when the seal means is moved to the flow preventing position.

Another object of this invention is to provide a controlled bypass wherein fluid pressure is used to enhance the action of the seal.

A further object of this invention is to provide a valve means for controlling fluid flow between axially aligned concentrically arranged tubular members in response to reciprocating movement of one of the tubular members.

A still further object of this invention is to provide a controlled bypass through an annular'chamber by reciprocatingly disposing a piston actuated seal within the chamber, wherein the chamber is formed between two coacting tubular members.

An additional object of this invention is the provision of a seal member for controlling fluid flow across a J- latch.

Another object of the invention is the provision of a seal means in combination with a tool having a .I-latch arranged in a manner to prevent fluid flow thereacross.

A still further object of the invention is the provision of a bypass for controlling fluid flow through a chamber which in turn controls the action of gripping elements.

- An additional object is the provision of a seal means in combination with a packer device, wherein the seal means is controlled by the action of a J-latch, and the seal means controls the action of gripping elements and at the same time precludes fluid flow across the J-latch.

These and various other objects and advantages of the invention will become readily apparent to those skilled in the art upon reading the following detailed description and claims and by referring to the accompanying drawings.

The above objects are attained in accordance with the present invention by the provision of a combination of elements which are fabricated in a manner substantially as described in the above abstract and summary.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary, part cross-sectional, side elevational view of a packer apparatus made in accordance with the present invention;

FIG. 2 is an enlarged, broken, part cross-sectional, side view of part of the apparatus disclosed in FIG. 1;

FIG. 3 is a broken, part cross-sectional, part dissembled side view of part of the apparatus disclosed in FIG. 2.

FIGS. 4 and 5, respectively, are cross-sectional views DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1 there is disclosed a retrievable packer apparatus 10 made in accordance with the present invention. The apparatus is supported within the interior of a well casing 11 by means of a tubing string 12. The tubing string is affixed to a housing disclosed herein as a sub 14 which diverges into a downwardly opening skirt member 16 having a lower peripheral edge portion 18. A port 20 is formed within the wall of the skirt member for enabling fluid to flow therethrough as will be better appreciated later on. Mandrel 22 is affixed to the sub 14 and slidably extends in a reciprocating or telescoping manner into a main body 24 of the packer apparatus.

The upper sub 26 of the main body has radially spaced outwardly directed J-pins 28 affixed thereto for engaging a J-slot located on the interior surface of the skirt member of the housing, the details of which will be more fully explained later on. Sub 30 of the main body contains a plurality of hydraulic hold-down gripping elements 32 which may be extended therefrom for engaging the casing when extended into contact therewith. Sub 34 of the main body supports two spaced expandable rubbers or packing elements 36, 36 in captured relationship thereon so that the packers can be extended into engagement with the interior wall of the casing by manipulation of the tubing string when it is desired to do so. Lower body portion 38 terminates in the form of a cone in proximity of lower mandrel portion 40 for facilitating the setting and releasing of a series of radially disposed slips 42. A plurality of radially disposed drag blocks 44 enables rotation of the mandrel with respect to the slips. The lowermost end portion 46 of the packer apparatus provides an outlet to which a tail pipe can be connected to thereby effect fluid flow from tubing 12 to the tubing which may be connected at 46.

For further details of the hydraulic hold-down, drag blocks, packer, and anchor, reference is made to the Clark Jr. et al and Keithahn patents referred to above.

Throughout the remaining figures of the drawing, wherever it is logical or practical to do so, like numerals relate to like or similar elements.

As seen in the illustrative example of FIGS. 2 to 6, an axial flow passageway 50 is formed through the entire packer assembly so that tubular elements 12 and 46 are inflow comunication with one another. The mandrel is axially aligned respective to skirt member 16 and the main body 24 with the main body having a reduced diameter upper marginal end portion 48 concentrically arranged with respect to the mandrel and to the skirt. The hollow mandrel flow communicates tubing 12 with tubing 46, while the exterior 52 of the mandrel is spaced from the interior wall surface 54 of the main body thereby forming an annular flow path 56 which enlarges into an annular working chamber 57, and reduces into an annular chamber seen at 58. Chamber 59 is jointly formed by the skirt member, mandrel, and main body.

A hollow piston 60 has a lower enlarged end portion, the exterior of which is sealed by means of O-ring 62 respective to the interior wall surface 57 of the main body. Interface 63 formed between the exterior piston wall and the interior wall of the main body has. sufficient tolerance to provide unbound slidable motion therebetween. The minor or interior wall surface 64 of the piston is spaced from the outer wall surface of the mandrel a sufficient amount to provide for the before mentioned flow passageway 58, also called a bypass. The upper marginal end portion of the piston is provided with a seal means in the form of an annular resilient body 66. Numeral 67 indicates the upper extremity of the piston travel relative to the main body.

As seen in FIG. 6, together with some of the remaining figures, the J-latch assembly is comprised of a J-slot 68 formed on the interior surface of the skirt member. The entrance 69 of the J-slot forms a groove within which the radially spaced pins 28 are received with the pens being guided along the illustrated groove until the slot reverses itself m7! and bottoms as indicated by numeral 70. The pin 28 can move with limited motion between the opposed walls 70, 70 in the usual manner, and accordingly, for this reason, the J-latch assembly is sometimes referred to as a lost motion coupling.

The hydraulic hold-down 32 can take on any number of different forms, and for purpose of illustration is disclosed as being a piston having an O-ring seal thereon for sealing and slidable engagement with a cylindrical aperture so that fluid pressure at 56 forces the piston in an outward direction.

As illustrated in FIG. 3, the before mentioned enlargement of the cylindrical piston is defined by opposed faces 72, 73 which abuttingly engage opposed faces 74, 76 which form the upper and lower end walls of the enlarged chamber 57.. The before mentioned seal 66 is preferably arranged at the upper end portion of the cylindrical piston and is comprised of a threaded ring member 80 having a circumferentially extending groove within which a resilient annular seal ring 66 is permanently affixed so that the resilient ring can sealingly engage seat 84 located on the sub 14. The relationship of the seal and seat may be reversed, if desired.

In the embodiments of FIGS. 7 and 8, the cylindrical piston is provided with a wafer-like gasket 182 attached by any suitable means to horizontal flange member which in turn is attached to the upper terminal end of the cylinder body. As seen in FIG. 8, seal face 84 of the housing can be set down on the seal ring 182 which bears against flange 180, with the flange bearing against the upper terminal end of the body portion 48.

With the J-latch assembly in the latched position of FIG. 8, it will be noted that the housing can be moved between the limits provided by the spaced walls 70, y

71. Assuming pressure to be exerted within passageway 57, the piston will be driven in an upward direction causing seals 84, 66 to engage one another because of the difference in pressure between passageway 57 and port 120, or the pressure as measured between the interior of the mandrel and the borehole annulus above the packer. As the housing is moved within limits of its lost motion coupling, the piston will travel therewith between the limits of travel afforded by spaced coacting faces of the'J-latch.

When installing the packer apparatus within a borehole, the apparatus is run downhole on a tubing string in the manner of FIG. 1. Where deemed desirable, a tail pipe can be placed at outlet 46 so as to enable fluid to be precisely spotted downhole. Upon reaching the proper depth the tubing 12 is rotated the proper number of revolutions in order to release the mandrel from the anchor and drag block housing thereby enabling the mandrel to move relatively downwardly to force the slips 42 into engagement with the casing wall. During this part of the operation the drag blocks 44 enable relative rotation to occur between the mandrel and the slips as the slips are turned out. After the bottom slips have been set, the mandrel is telescoped down enabling the top J to be latched as each of the pins 28 is received within one of the slots 68, with the pins being guided along wall 70' in the usual manner of a J assembly.

As the mandrel is telescoped down the skirt member 8 portion 26 of the main body, and sea] surface 84 of the housing moves toward seal member 66 of the cylindrical piston. As the weight of the tubing string is set down upon the main body, the packer elements pack-off the lower portion of the borehole in the usual manner. As pressure is applied to the tubing string, flow occurs through the mandrel, through the outlet at 46, into the borehole annulus, back into passageway 56, into chamber 57, passageway 58, chamber 59, across the Match asembly, and through port 20. The pressure drop across the piston forces the piston to move in an upward direction until shoulders 72 and 74 abut one another, or until seal 66 abuts surface 84. The occurrence of the last two alternate actions depends upon the location of pin 28 relative to the .I-slot. In the preferred embodiment of FIGS. 2 and 8, when the pin is turned out of the J-slot, the seal 66 is displaced from and cannot abut seat 84 and accordingly fluid will bypass the seal means by flowing from passageway 58, about the piston seal, and through port 20. Alternatively, where the J is latched and the pin is positioned in the groove defined by walls 70, 70, the seal 66 will abut the seat or annular shoulder 84, within the limits of reciprocation as indicated between numerals 66 and 67, for example. Therefore, the movement which is permitted between the skirt member and the main body before the bypass check valve will permit flow of fluid about the seal means is equal to the movement of the pin within the latched J. I

In any event, when the tubing string is set down so that shoulder 84 contacts seal 66, a seal is effected therebetween, and the piston will travel along with the skirt member within the before described limits so long as a sufficient pressure differential is maintained thereacross.

In FIGS. 7 and 8, the relative distance between walls 70, 70' and 71 and the relationship between walls 72 and 74 therewith is arranged so that the'piston is always placed in sealing engagement with the seat, so long as the J-latch is turned in. In FIG. 8, for example, it will be noted that the distance between shoulders 72 and 74 is equal to the distance between walls 70 and 70' and accordingly the seal and seat are always in sealed relationship so long as the J is in the latched configuration. Therefore, the piston will follow the skirt as the tubing is reciprocated relative to the main body, if sufficient pressure is effected within the tubing string. In this alternate embodiment, the tubing string can also be used to open the bypass only upon unlatching the J." In either embodiment, closure of the bypass arrangement causes the gripping elements to move outward respective to bore 75, and vice versa. In spotting fluid downhole in a borehole, the tool is set in the running in position. Where the packer and anchor device at 42 is of the type taught in Clark Jr. et al, or a Baker Model R product No. 642-0l for example, it will be necessary to have the bottom J in the latched configuration, with the anchor in the retracted configuration, and with the J of the present invention in the unlatched configuration. Upon reaching the desired elevation, the bottom J" is turned out (the tubing is manipulated or turned to unlatch the bottom J and for this reason, drag blocks or drag elements are utilized. After the bottom slips or anchor device has been set, the mandrel is telescoped down thereby enabling the top J to be latched. This causes the seal means of the present invention to move into engagement with one another and at the same time, packer element 36 moves outwardly into engagement with the wall of the casing. With the weight of the tubing string continuing to maintainthe packer elements in the expanded configuration, pressure is applied to the tubing string. As pressure is applied to the tubing string, it is effected at annulus 56 and 57, thereby causing the pistom 63 to move in an upward direction respective to its body whereupon the seal engages the shoulder and precludes fluid flow across the upper J.'Since fluid can no longer flow through the annulus 58, the pressure differential across the packer is also effected across the gripping elements 32 and accordingly, the gripping elements move into gripping relationship with the interior of the casing.

Should the pressure be removed from the tubing 12, the gripping elements will relax and the piston could possibly become unsealed from it seat, depending upon the location of the pin within its J slot, or the travel provided at 66, 67, and 72, 74. Nevertheless, when pressure is again applied to the tubing string, the piston will again be pumped back into engagement with the seat, thereby precluding fluid flow across the J latch.

Accordingly, it is evident that the lost motion coupling can be unlatched to enable the tubing 12 to be lifted vertically upward at any time in order to break the seal between the piston and the seat. This expedient enables the retrievable packer to be rapidly located at various elevations within the borehole.

I claim:

1. A packer apparatus for use downhole in a borehole and which is adapted to be anchored in a well casing, said apparatus having a body, a hollow mandrel slidably received within said body, a housing attached to said mandrel and movable therewith, means forming a lost motion coupling connecting said housing to said body in a manner to permit said housing to be moved axially from a first to a second position relative to said body;

means forming a packer element on said body for expansion outwardly into sealing engagement with a well casing and means connected to said mandrel and to said body for causing said packer element to expand outwardly when said mandrel is moved downhole relative to said body;

said mandrel, housing, and body cooperatively forming an annular chamber therebetween;

means forming a flow passageway for conducting fluid flow into the packer body at a location below said packer elements, into said annular chamber, and'through said housing;

a piston reciprocatingly received within said annular chamber, at least part of said piston being disposed within at least part of said housing when said housing is in the first position; seal means on said piston for preventing fluid flow through said flow passageway when said housing is in the first position and for permitting fluid flow through said flow passageway when said housing is in the second position.

2. The apparatus of claim 1 wherein said housing includes a skirt member, said skirt member being circumferentially disposed about and spaced from said mandrel, said body having an upper marginal end portion which is received within said housing when the housing is in the first position;

said annular chamber having an upper portion and an enlarged lower portion, said piston having an upper portion and an enlarged lower portion, with the upper portion of said piston being received within said upper portion of said annular chamber, and said enlarged lower portion of said piston being received within the lower enlarged portion of said annular chamber;

the lower enlarged portion of said piston having spaced shoulders, said lower enlarged portion of said annular chamber having spaced shoulders against which said spaced shoulders of said piston abut as the piston reciprocates within the annulus, to thereby limit the piston travel.

3. The apparatus of claim 1, wherein said flow passageway includes a longitudinal flow path formed between the mandrel and the main body, the last said flow path communicating said annular chamber with a fluid pressure which may be present in a well bore below said packer element;

means forming radially spaced bores within said body, said bores communicating the last said flow path with the exterior of the apparatus; and gripping elements reciprocatingly received within said bores and preventing fluid flow therethrough.

4. The apparatus of claim 1 wherein said lost motion coupling is in the form of a .l-latch assembly;

said housing having means forming a skirt which is spaced from the mandrel; said body having a marginal edge portion received within a marginal edge portion ofsaid skirt;

said means forming a flow passageway being arranged to flow connect said annular chamber with a a lower extremity of the packer body;

radially spaced bores formed in said main body, said bores being in flow communication with said flow passageway and with the exterior of an upper portion of the apparatus; grippingelements sealingly and reciprocatingly received within said bores and movable outwardly away from said mandrel when sufficient pressure is effected in said passageway;

a port formed in said skirt for the recited fluid flow from said passageway.

5. The apparatus of claim 1 wherein said lost motion coupling is a .l-latch, and said first position of said piston relates to said .l-latch being in the latched configuration while said second position relates to said J-latch being in the disengaged position;

said flow passageway includes a longitudinal flow path formed between the mandrel and the main body, said flow path communicating said annular chamber with a fluid pressure which may be pres ent in a'well bore below said packer element; means forming bores spaced radially within said body, said bores communicating the last said flow path with the exterior of the apparatus; and means forming gripping elements which are reciprocatingly received with said bores and prevent flow of fluid therethrough.

6. The apparatus of claim 1 wherein said lost motion coupling is a Match, said J-latch being in the latched configuration when said housing is in the first position; said J-latch being in the disengaged position when said housing is in the second position;

said housing includes a skirt which is circumferentially disposed about and spaced from said mandrel, said body having an upper marginal end portion received within said housing;

said annular chamber forming an annulus having an upper and an enlarged lower-portion, said piston having an upper and an enlarged lower portion, with the upper portion of said piston being received within said upper portion of said annulus, and said enlarged lower portion of said piston being received within the lower enlarged portion of said annulus;

the lower enlarged portion of said piston having spaced shoulders, said lower enlarged portion of said annulus having spaced shoulders against which said spaced shoulders of said piston abut as the piston reciprocates within the annulus.

7. Apparatus for controlling fluid flow across a lost motion coupling comprising a mandrel, a housing affixed to said mandrel, a body having means forming a piston chamber therein, and a piston reciprocatingly received within said piston chamber;

said housing including a skirt which is spaced from the mandrelto form a portion of said piston chamber; said body being circumferentially disposed about said mandrel and having a marginal portion thereof received by said skirt; said marginal portion of said body being spaced from said mandrel and forming a portion of said piston chamber; said piston being concentrically arranged respective to said mandrel, body, and skirt, said piston being reciprocatingly received within a portion of said skirt and within a portion of said main body;

seal means on said piston and on said housing for sealingly engaging one another when said piston is reciprocated into a first position, and for being disengaged from one another when said piston is reciprocated into another position;

means limiting the travel of said piston relative to said body; a lost motion coupling means by which said housing is removably connected movement to said body; and,

a flow passageway means connected to the piston chamber so as to form an inlet and outlet for flow of fluid therethrough when the piston is reciprocated awayfrom the seal means on said housing.

8. The apparatus of claim 7 wherein said seal means on said piston and on said housing includes:

a circumferentially extending seal means axially aligned relative to said mandrel and affixed to said housing;

a circumferentially extending seal means affixed to an upper portion of the piston and axially aligned relative to said mandrel and aligned with the seal means on said housing;

the seal means on the piston being moved into engagement with the seal means on the housing when said mandrel is moved axially respective to said body.

9. A packer apparatus adapted to be connected to a tubing string and anchored within a borehole by manipulation of the tubing string, said apparatus having a main body, a mandrel slidably received within said main body, a housing affixed to said mandrel and movable therewith, means forming a J-latch for releasably connecting said housing to said main body;

said mandrel, housing, and main body cooperatively forming an annular chamber therebetween, a piston means reciprocatingly received within said-annular chamber, seel means disposed on said housfor limited ing within said annular chamber, seal means on said piston means which engages said seal means on said housing when said piston means is reciprocated into engagement therewith;

an anchor device for anchoring the packer apparatus within a borehole;

said packer apparatus including means forming packer elements for expansion outwardly into sealing engagement with the well casing; means connected to said mandrel and said main body for actuating said anchor device and thereafter causing said packer elements to expand outwardly into engagement with the wall of the well casing.

10. The packer apparatus of claim 9 wherein said housing includes a skirt which is circumferentially dis- 10 being received within 'said upper portion of said annulus, and said enlarged lower portion of said piston means being received within the lower enlarged portion of said annulus;

the lower enlarged portion of said piston means having spaced apart shoulders, said lower enlarged portion of said annulus having spaced apart shoulders against which said spaced apart shoulders of said piston means abut as the piston means reciprocates within the annulus.

11. The packer apparatus of claim 10 wherein a longitudinal flow path is formed between the mandrel and the main body, said flow path communicating said annular chamber with a fluid pressure which may be present in a well bore below said packer element;

means forming radially spaced bores within said body, said bores communicating said flow path with the exterior of the apparatus; and gripping elements reciprocatingly received within said bores and preventing fluid flow therethrough. 

1. A packer apparatus for use downhole in a borehole and which is adapted to be anchored in a well casing, said apparatus having a body, a hollow mandrel slIdably received within said body, a housing attached to said mandrel and movable therewith, means forming a lost motion coupling connecting said housing to said body in a manner to permit said housing to be moved axially from a first to a second position relative to said body; means forming a packer element on said body for expansion outwardly into sealing engagement with a well casing and means connected to said mandrel and to said body for causing said packer element to expand outwardly when said mandrel is moved downhole relative to said body; said mandrel, housing, and body cooperatively forming an annular chamber therebetween; means forming a flow passageway for conducting fluid flow into the packer body at a location below said packer elements, into said annular chamber, and through said housing; a piston reciprocatingly received within said annular chamber, at least part of said piston being disposed within at least part of said housing when said housing is in the first position; seal means on said piston for preventing fluid flow through said flow passageway when said housing is in the first position and for permitting fluid flow through said flow passageway when said housing is in the second position.
 2. The apparatus of claim 1 wherein said housing includes a skirt member, said skirt member being circumferentially disposed about and spaced from said mandrel, said body having an upper marginal end portion which is received within said housing when the housing is in the first position; said annular chamber having an upper portion and an enlarged lower portion, said piston having an upper portion and an enlarged lower portion, with the upper portion of said piston being received within said upper portion of said annular chamber, and said enlarged lower portion of said piston being received within the lower enlarged portion of said annular chamber; the lower enlarged portion of said piston having spaced shoulders, said lower enlarged portion of said annular chamber having spaced shoulders against which said spaced shoulders of said piston abut as the piston reciprocates within the annulus, to thereby limit the piston travel.
 3. The apparatus of claim 1, wherein said flow passageway includes a longitudinal flow path formed between the mandrel and the main body, the last said flow path communicating said annular chamber with a fluid pressure which may be present in a well bore below said packer element; means forming radially spaced bores within said body, said bores communicating the last said flow path with the exterior of the apparatus; and gripping elements reciprocatingly received within said bores and preventing fluid flow therethrough.
 4. The apparatus of claim 1 wherein said lost motion coupling is in the form of a J-latch assembly; said housing having means forming a skirt which is spaced from the mandrel; said body having a marginal edge portion received within a marginal edge portion of said skirt; said means forming a flow passageway being arranged to flow connect said annular chamber with a lower extremity of the packer body; radially spaced bores formed in said main body, said bores being in flow communication with said flow passageway and with the exterior of an upper portion of the apparatus; gripping elements sealingly and reciprocatingly received within said bores and movable outwardly away from said mandrel when sufficient pressure is effected in said passageway; a port formed in said skirt for the recited fluid flow from said passageway.
 5. The apparatus of claim 1 wherein said lost motion coupling is a J-latch, and said first position of said piston relates to said J-latch being in the latched configuration while said second position relates to said J-latch being in the disengaged position; said flow passageway includes a longitudinal flow path formed between the mandrel and the main body, said flow path communicating said annular chamber with a fluid pressure which may be Present in a well bore below said packer element; means forming bores spaced radially within said body, said bores communicating the last said flow path with the exterior of the apparatus; and means forming gripping elements which are reciprocatingly received with said bores and prevent flow of fluid therethrough.
 6. The apparatus of claim 1 wherein said lost motion coupling is a J-latch, said J-latch being in the latched configuration when said housing is in the first position; said J-latch being in the disengaged position when said housing is in the second position; said housing includes a skirt which is circumferentially disposed about and spaced from said mandrel, said body having an upper marginal end portion received within said housing; said annular chamber forming an annulus having an upper and an enlarged lower portion, said piston having an upper and an enlarged lower portion, with the upper portion of said piston being received within said upper portion of said annulus, and said enlarged lower portion of said piston being received within the lower enlarged portion of said annulus; the lower enlarged portion of said piston having spaced shoulders, said lower enlarged portion of said annulus having spaced shoulders against which said spaced shoulders of said piston abut as the piston reciprocates within the annulus.
 7. Apparatus for controlling fluid flow across a lost motion coupling comprising a mandrel, a housing affixed to said mandrel, a body having means forming a piston chamber therein, and a piston reciprocatingly received within said piston chamber; said housing including a skirt which is spaced from the mandrel to form a portion of said piston chamber; said body being circumferentially disposed about said mandrel and having a marginal portion thereof received by said skirt; said marginal portion of said body being spaced from said mandrel and forming a portion of said piston chamber; said piston being concentrically arranged respective to said mandrel, body, and skirt, said piston being reciprocatingly received within a portion of said skirt and within a portion of said main body; seal means on said piston and on said housing for sealingly engaging one another when said piston is reciprocated into a first position, and for being disengaged from one another when said piston is reciprocated into another position; means limiting the travel of said piston relative to said body; a lost motion coupling means by which said housing is removably connected for limited movement to said body; and, a flow passageway means connected to the piston chamber so as to form an inlet and outlet for flow of fluid therethrough when the piston is reciprocated away from the seal means on said housing.
 8. The apparatus of claim 7 wherein said seal means on said piston and on said housing includes: a circumferentially extending seal means axially aligned relative to said mandrel and affixed to said housing; a circumferentially extending seal means affixed to an upper portion of the piston and axially aligned relative to said mandrel and aligned with the seal means on said housing; the seal means on the piston being moved into engagement with the seal means on the housing when said mandrel is moved axially respective to said body.
 9. A packer apparatus adapted to be connected to a tubing string and anchored within a borehole by manipulation of the tubing string, said apparatus having a main body, a mandrel slidably received within said main body, a housing affixed to said mandrel and movable therewith, means forming a J-latch for releasably connecting said housing to said main body; said mandrel, housing, and main body cooperatively forming an annular chamber therebetween, a piston means reciprocatingly received within said annular chamber, seel means disposed on said housing within said annular chamber, seal means on said piston means which engages said seal means on said housing when said pistOn means is reciprocated into engagement therewith; an anchor device for anchoring the packer apparatus within a borehole; said packer apparatus including means forming packer elements for expansion outwardly into sealing engagement with the well casing; means connected to said mandrel and said main body for actuating said anchor device and thereafter causing said packer elements to expand outwardly into engagement with the wall of the well casing.
 10. The packer apparatus of claim 9 wherein said housing includes a skirt which is circumferentially disposed about and spaced from said mandrel, said body having an upper marginal end portion received within said housing; said annular chamber forming an annulus having an upper and an enlarged lower portion, said piston means having an upper and an enlarged lower portion, with the upper portion of said piston means being received within said upper portion of said annulus, and said enlarged lower portion of said piston means being received within the lower enlarged portion of said annulus; the lower enlarged portion of said piston means having spaced apart shoulders, said lower enlarged portion of said annulus having spaced apart shoulders against which said spaced apart shoulders of said piston means abut as the piston means reciprocates within the annulus.
 11. The packer apparatus of claim 10 wherein a longitudinal flow path is formed between the mandrel and the main body, said flow path communicating said annular chamber with a fluid pressure which may be present in a well bore below said packer element; means forming radially spaced bores within said body, said bores communicating said flow path with the exterior of the apparatus; and gripping elements reciprocatingly received within said bores and preventing fluid flow therethrough. 